[java] Sent message: This is text message A 0
[java] Sent message: This is text message A 1
[java] Sent message: This is text message A 2
[java] Sent message: This is text message A 3
[java] Sent message: This is text message A 4
[java] Sent message: This is text message A 5
[java] Sent message: This is text message A 6
[java] Sent message: This is text message A 7
[java] Sent message: This is text message A 8
[java] Sent message: This is text message A 9
[java] Sent message: This is text message B 10
[java] Sent message: This is text message B 11
[java] Sent message: This is text message B 12
[java] Sent message: This is text message B 13
[java] Sent message: This is text message B 14
[java] Sent message: This is text message B 15
[java] Sent message: This is text message B 16
[java] Sent message: This is text message B 17
[java] Sent message: This is text message B 18
[java] Sent message: This is text message B 19
[java] Got message: This is text message A 0 from node 0
[java] Got message: This is text message B 11 from node 1
[java] Got message: This is text message A 2 from node 0
[java] Got message: This is text message B 13 from node 1
[java] Got message: This is text message A 4 from node 0
[java] Got message: This is text message B 15 from node 1
[java] Got message: This is text message A 6 from node 0
[java] Got message: This is text message B 17 from node 1
[java] Got message: This is text message A 8 from node 0
[java] Got message: This is text message B 19 from node 1
[java] example complete

You can see how messages are being left on the queues since the selectors didn't happen to match on that node.